Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain McDonnell Douglas Model MD-11 series airplanes, that currently requires visual inspections to detect cracking of the outboard and inboard surfaces of the upper spar angles of the wing pylons, and repair of any cracked upper spar angles. This action would require eddy current inspections to detect cracking of the upper spar angles on the left and right sides of the wing pylons, and replacement of the spar angles as terminating action for the inspections. This proposal is prompted by the development of a modification that positively addresses the unsafe condition. The actions specified by the proposed AD are intended to prevent loss of load-carrying and fail-safe capability of the upper inboard spar cap of the wing pylon, which could subsequently reduce the structural integrity of the airplane.